林业科学2017，Vol.53Issue(12)：20-29,10.DOI:10.11707/j.1001-7488.20171203
安庆地区大气降水氢氧同位素特征及水汽来源
Characteristics of δD andδ18O in the Precipitation and Evaporation Sources in Anqing
摘要
Abstract
[Objective] It is critical to examine the characteristics of hydrogen (δD) and oxygen (δ 18O) stable isotopes in the precipitation as well as the source and migration process of regional atmospheric precipitation in Anqing that help reveal the mechanism of the hydrological cycle in the forest ecosystem of Anhui Province along the Yangtze River in response to climate change.[Method] Using a stable isotope technique,we analyzed the compositions of δD and δ 18O in 155 precipitation samples between June 2015 and June 2017 in Anqing,and examined the local meteoric water line.To analyze whether and how the climatic factor affects the compositions of δD and δ 18O in the precipitation,we established the relationships of δD (δ 18O) to the precipitation and temperature.We traced the sources of atmospheric water in Anqing by calculating the D-excess (d) in the precipitation,and verified the results of the sources through HYSPLIT model.[Result] The relationship between δD and δ 18O in the precipitation in Anqing was δD =(8.08 ± 0.06)δ 18O + (10.84 ±0.48) (R2 =0.99,n =155).The stable isotopes δD and δ 18O were significantly negatively associated with temperature (P ＜ 0.01),while no significant correlation was found between the stable isotopes and the precipitation (P ＞ 0.05).The D-excess(d) was close to the global average (10‰),suggesting that the precipitation in the area was mainly affected by the ocean monsoon.The results of air mass back trajectories of the precipitation were calculated by the HYSPLIT model and showed that there were different sources of atmospheric vapor in Anqing.In spring,the atmospheric vapor was affected by the local evaporation and continental air mass from north and south China,and was likely influenced by the Pacific southeast monsoon when rainfall was heavy.In other seasons,atmospheric vapor sources were mainly impacted by the South China Sea air mass,Pacific southeast monsoon,and southwest monsoon of India Ocean.[Conclusion] In this study,the precipitation in Anqing was primarily influenced by atmospheric vapor from the ocean.Differing from the traditional stable isotopes theory of temperature effect,a opposite temperature effect was found in the precipitation in Anqing,this is probably attributable to the latitudes of Anqing,suggesting that different geographical locations probably influenced the composition of δD and δ 18O in the precipitation.Therefore,further studies understand the influences are needed.关键词
安庆地区/大气降水/氢氧稳定同位素/过量氘/相对湿度/气团轨迹/水汽来源Key words
Anqing/meteoric water/hydrogen and oxygen stable isotopes/D-excess/relative humidity/water vapor trajectory/water resource分类
农业科技引用本文复制引用
张蓓蓓,徐庆,姜春武..安庆地区大气降水氢氧同位素特征及水汽来源[J].林业科学,2017,53(12):20-29,10.基金项目
林业公益行业专项(201504423) （201504423）
国家自然科学基金项目(31670720) （31670720）
科技部农业成果转化资金项目(2013GB24320620). （2013GB24320620）
